Lately, many consumers have formed primary financial relationships without relying on traditional financial institutions, opting to turn to mobile bank accounts for a primary or secondary household checking account.

Major non-bank players have responded to those choosing to escape brick-and-mortar financial institutions while avoiding overdraft fees.

As competitors in the financial services industry grow, stricter regulations on fees have also changed the face of checking. Courtesy pay opt-in has cut the number of members with automatic overdraft protection. Because overdraft fees are still the largest source of noninterest income revenue for many credit unions, that's a big concern for some.